The Panama based client had a requirement to replace radiographic testing with an automatic encoded ultrasonic system in accordance with ASME Code Case 2235 due to the difficulties in obtaining a license for using radiographic isotopes in Central America.
Phased array ultrasonic testing (PAUT) was selected as the automated ultrasonic testing technique for its ability to use multiple elements to steer, focus and scan beams with a single transducer assembly. PAUT also has a higher probability of detection (POD) especially for cracks and lack of fusion. The inspection speed is greatly reduced with the use of encoded scanners. A full validation was performed in accordance with ASME code case 2235 under the witness of Lloyds China, where numerous welded samples containing seeded defects were successfully scanned & analysed.
Changing to an automated ultrasonic technique means that